Method of making an interior trim panel

ABSTRACT

A method of making an interior trim panel for attachment to structure of a vehicle includes the steps of loading a trim blank into a cavity of a first side of a mold and depositing a molten thermoplastic material onto a core on the first side of the mold. The method also includes the steps of closing the mold, moving the slide in a channel of the core, and injecting a molten thermoplastic material into a second side of the mold to form the interior trim panel.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present invention claims the priority date of copending U.S.Provisional Patent Application Ser. No. 60/173,636, filed Dec. 30, 1999.

TECHNICAL FIELD

The present invention relates generally to interior trim panels forvehicles and, more particularly, to a method of making an interior trimpanel for a vehicle.

BACKGROUND OF THE INVENTION

It is known to provide an interior trim panel for a vehicle to presentan aesthetically pleasing appearance in an occupant compartment of thevehicle. The interior trim panel typically includes a trim blankattached to a carrier or substrate by several different conventionalprocesses including adhesives, heat staking, sonic welding, andfasteners. The interior trim panel may be mounted to structure of thevehicle such as an inner door panel of a door for the vehicle bysuitable means such as fasteners.

Although the above interior trim panel and method of making has worked,it is desirable to reduce the costs associated with the manufacture ofan interior trim panel. It is also desirable to provide an interior trimpanel with reduced mass, tooling, and equipment per vehicle. Therefore,there is a need in the art to provide an improved method of making aninterior trim panel for a vehicle.

SUMMARY OF THE INVENTION

It is, therefore, one object of the present invention to provide a newmethod of making an interior trim panel for a vehicle.

It is another object of the present invention to provide a method ofmaking an interior trim panel that combines extrusion deposition andinjection molding into a single step.

It is yet another object of the present invention to provide a method ofmaking a door trim panel that has less cost.

To achieve the foregoing objects, the present invention is a method ofmaking an interior trim panel for attachment to structure of a vehicle.The method includes the steps of loading a trim blank into a cavity of afirst side of a mold and depositing a molten thermoplastic material ontoa core on the first side of the mold. The method also includes the stepsof closing the mold, moving the slide in a channel of the core, andinjecting a molten thermoplastic material into a second side of the moldto form the interior trim panel.

One advantage of the present invention is that an improved method ofmaking an interior trim panel is provided for a vehicle. Anotheradvantage of the present invention is that the method of making theinterior trim panel is a lean manufacturing method with in-moldlamination for obtaining a trim panel which is partially clad with trimwhile another area is grained, molded in color (class A interiorsurface) in a single step process using the same equipment. Yet anotheradvantage of the present invention is that the method of making theinterior trim panel reduces cost as opposed to a two-piece constructionand by using a lower-cost, uncolored, material for Side A, including thepossible use of multi-color regrind. Still another advantage of thepresent invention is that the method of making the interior trim panelreduces material cost by using low cost material behind the trim coverarea and more structural material at a lower cost. A further advantageof the present invention is that the method of making the interior trimpanel provides good surface appearance at a junction of the trim andstraight injection molded surface. Yet a further advantage of thepresent invention is that the method of making the interior trim panelprovides ease of processibility and design flexibility by providing anopportunity to design trim panels with less cost.

Other objects, features, and advantages of the present invention will bereadily appreciated, as the same becomes better understood, afterreading the subsequent description taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an interior trim panel made by a method, according to thepresent invention, illustrated in operational relationship with avehicle.

FIG. 2 is a fragmentary side view of a mold used in a method, accordingto the present invention, of making the interior trim panel of FIG. 1illustrated in an open position.

FIG. 3 is a partial fragmentary view of a movable slide of the mold ofFIG. 2 illustrated in a first position with the mold closed.

FIG. 4 is a partial fragmentary view of a movable slide of the mold ofFIG. 2 illustrated in a second position with the mold closed.

FIG. 5 is a fragmentary side view of the mold of FIG. 2 illustrated inan open position.

FIG. 6 is a fragmentary side view of the mold of FIG. 2 illustrated in aclosed position for molding of side A of the interior trim panel.

FIG. 7 is a fragmentary side view of the mold of FIG. 2 illustrated in aclosed position for molding of side B of the interior trim panel.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings and in particular FIG. 1, one embodiment of aninterior trim panel 10, according to the present invention, is shownmounted to structure such as a door 12 of a vehicle 14 such as anautomotive vehicle. It should be appreciated that, in this example, theinterior trim panel 10 is mounted to an inner panel 16 of the door 12.It should also be appreciated that the interior trim panel 10 may bemounted to other structure or panels of the vehicle 14.

Referring to FIGS. 1 and 7, the interior trim panel 10 includes acarrier 18 extending longitudinally and vertically and having agenerally rectangular shape. The carrier 18 is made of a thermoplasticmaterial such as polypropylene. The carrier 18 is formed by a method,according to the present invention, to be described. The carrier 18 hasan inner side 20 and an outer side 22. The carrier 18 has a projection24 formed adjacent an edge of a trim blank 26 to be described. The outerside 22 is attached to the inner panel 16 of the door 12 by suitablemeans such as fasteners (not shown). It should be appreciated that thecarrier 18 is partially clad with the trim blank 26 to be described forthe interior trim panel 10.

The interior trim panel 10 also includes a trim blank 26 incorporated orintegrated into the carrier 18. The trim blank 26 extends longitudinallyand vertically. The trim blank 26 is made of a fabric, cloth, vinyl, TPO(Thermoplastic Polyolifin), leather, or carpet material. Preferably, thetrim blank 26 is pre-cut or pre-blanked by a conventional process knownin the art. The trim blank 26 is disposed over and bonded to the innerside 20 of the carrier 18 by melting and fusion of the plastic materialof the carrier 18. It should be appreciated that the trim blank 26covers only a portion on one side of the projection 24 of the carrier18. It should also be appreciated that the trim blank 26 is a separatepiece or component.

Referring to FIGS. 2 through 7, a method, according to the presentinvention, of making the interior trim panel 10 is disclosed. The methodinvolves combining extrusion deposition compression molding (EDCM) withinjection molding or injection-compression molding (ICM). Asillustrated, a mold, generally indicated at 30, includes a first halfmold 32 and a second half mold 34. The first half mold 32 is the moldcavity and the second half mold 34 is the mold core. The first half mold32 has a cavity portion 33 and the second half mold 34 has a coreportion 35. The first half mold 32 and second half mold 34 could bemounted to platens (not shown) of a press (not shown) such as a verticalmolding press with sufficient tonnage to accomplish the method to bedescribed with the cavity up or cavity down. The first half mold 32 hasa trim loading system 36 such as a slip device or pin frame, preferablya three-sided pin frame. The trim loading system 36 accommodates loadingof the trim blank 26 as part of an insert molding process and may be aslip frame or manual loading system. The second half mold 34 has aninlet 38 and a passage 40 for allowing a fluid material such as moltenplastic or plastic melt to enter between the first and second half molds32 and 34. The mold 30 also includes a movable slide 42 movable along achannel 44 in the second half mold 34 between an extended position asillustrated in FIG. 3 and a retracted position as illustrated in FIG. 4.The slide 42 has a groove or recess 46 therein for a function to bedescribed. The mold 30 further includes a blade 48 extending along thefirst half mold 32 and cooperating with the recess 46 of the slide 42.It should be appreciated that, for purposes of description, the mold 30will have two sides or portions A and B on the first half mold 32 andsecond half mold 34. It should also be appreciated that the side A willbe the area of the interior trim panel 10 to be covered by the trimblank 26 and side B will be the area of the interior trim panel 10 tohave an interior “Class A” surface.

The method, according to the present invention, includes the step ofloading the trim blank 26 onto the cavity portion 33 of the first halfmold 32 on side A as illustrated in FIG. 2. The trim blank 26 can beunformed or preformed using known thermoforming processes. The methodincludes the step of moving the slide 42 by extending the slide 42 intothe cavity area, separating side A from side B in the mold 30 asillustrated in FIG. 3. The method includes the step of providing a ECDMdeposition unit 50 with an extrusion head with X-Y-Z axis positioningcapability and depositing by extruding a plastic melt as a strand or asheet in the mold area or core portion 35 corresponding to side A of thefinished interior trim panel 10 onto the second half mold 44 asillustrated in FIG. 5. The method includes the step of closing the mold30 and causing the plastic melt to flow and fill side A of the moldcavity and resulting in adhesion to the back of the trim blank 26 whileit is formed into the shape of the mold cavity (if not preformed) asillustrated in FIG. 6. The blade 48 is disposed in the recess 46 of theslide 42 and prevents overflow of the plastic melt to form a portion ofthe projection 24. It should be appreciated that the projection 24 willprovide a sharp distinction of the trim blank 26 adjacent to themolded-in-color show surface of the carrier 18.

The method includes the step of providing a fixed injection unit 54,positioned to inject molten plastic directly into the inlet or sprue 38on the side of the second half mold 34. The method includes the step ofmoving the slide 42 by retracting the slide 42 away from the blade 48 asillustrated in FIG. 4. The method includes the step of injecting plasticmelt from the fixed injection unit 54, which flows through the passage40 into the mold cavity on side B, filling side B as illustrated in FIG.7. The method includes cooling the mold 30 for a required cooling timeand opening the mold 30 and removing the partially clad, molded interiortrim panel 10.

Alternatively, as the movable slide 42 between side A and side B isretracted, the mold 30 is opened slightly and plastic melt is injectedfrom the fixed injection unit 54, filling side B of the panel. The mold30 is then fully closed, causing the molding plastic to completely fillside B of the mold cavity. It should be appreciated that these steps aresimilar to injection compression molding (ICM).

Accordingly, the method provides the combination of extrusion depositionmolding and injection molding in a single manufacturing step to make atrim panel, which is partially covered, and partially exposed having aclass A interior surface. The method also prevents overflow of the meltduring EDCM step and to have sharp distinction of the trim materialadjacent to the molded-in-color show surface.

The present invention has been described in an illustrative manner. Itis to be understood that the terminology, which has been used, isintended to be in the nature of words of description rather than oflimitation.

Many modifications and variations of the present invention are possiblein light of the above teachings. Therefore, within the scope of theappended claims, the present invention may be practiced other than asspecifically described.

1. A method of making an interior trim panel for a vehicle, said methodcomprising the steps of: providing a mold having a first half and asecond half; providing a trim loading system on the first half;pre-cutting a trim blank; loading the trim blank into the trim loadingsystem; moving a slide having a recess to an extended position on thesecond half to divide the second half into two sides; extruding a moltenfirst thermoplastic material onto the side of the second half that isopposite the trim blank; closing the mold to bond the firstthermoplastic material to the trim blank to form a cavity on the side ofthe second half not containing the first thermoplastic material and trimblank and disposing a blade on the first half into the recess of theextended slide; moving the slide to a retracted position; injecting amolten second thermoplastic material into the cavity between the firsthalf and the second half to bond the second thermoplastic material tothe first thermoplastic material to form the interior trim panel; andopening the mold.
 2. A method as set forth in claim 1 wherein said stepof injecting comprises providing an injection unit for injecting moltenplastic into the mold.
 3. A method as set forth in claim 2 including thestep of cooling the interior trim panel.
 4. (canceled)
 5. A method asset forth in claim 4 including the step of removing the interior trimpanel from the mold.
 6. A method as set forth in claim 1 including thestep of starting one step before a previous step has been completed.